1. Field of the Invention
The present invention relates to a building material which may be used for making floors in industrial, public and residential buildings. Specifically, the present invention relates to a magnesia concrete.
2. Prior Art
U.S.S.R. Inventor's Certificate no. 749809 disclosed a magnesia concrete which consists of the following components, by weight:
______________________________________ Magnesium oxide 5-6.5 parts Magnesium chloride 3.5-4.2 parts Futile spirit 0.03-0.06 parts Slag-heap from the copper- 8-10 parts nickel production industry Calcium chloride 0.7-1.2 parts Mineral aggregate 7-9 parts ______________________________________
The floors using this mixture were of high-strength and were water-resistant. However, during the usage of these floors, the calcium chloride which is in an uncombined state was washed out. Thus, this decreased the floor's quality and caused the floors to prematurely fall apart.
In a second U.S.S.R. Inventor's Certificate, no. 923993, another magnesia concrete was taught which consists of the following components, by weight:
______________________________________ Magnesium oxide 4-5 parts Magnesium chloride 2.5-3.5 parts Mineral aggregate 18-30 parts Carbonate-contained slime 1.0-1.5 parts Ethyl ether of a orthosilicic 0.05-0.07 parts acid ______________________________________
Although, the silicon-organic admixture added to this mixture reduces hydroscopicity of the floor and increases its water resistance, the carbonate-contained slime which has alkaline properties prevents the full process of the magnesium oxychloride formation. Consequently, this leads to deterioration of the parameters of the floors.
In addition, the floors made of either of the above-mentioned compositions have a comparatively high penetrability to oil products. Thus, this limits the field of use of the floors.
The relatively large amounts of magnesium chloride and the fact that the water solution of the required concentration should be prepared beforehand are also shortcomings of these known cements.
In the past aluminum chloride and iron have been used in the cement-concrete mixtures as setting accelerator for portland cement.
It is also known that sodium siliceous-fluoride is used in combination with water glass as a setting catalyst for the latter.